Washington, Oct 12 (IANS): A six-day-old rare female panda cub who died recently at the US zoo had met with its end due to a liver failure, authorities have said.

The cub's sudden death had attracted widespread public attention in Russia last month.

The US National Zoo in Washington said Thursday that liver failure caused the recent sudden death of a six-day-old rare female panda cub, an event which captured national attention last month.

Chief veterinarian Suzan Murray said a necropsy performed on the cub showed that it died from liver necrosis, or the death of liver cells.

The zoo, in a press release, said it was lung and liver damage that ultimately killed the cub: "Her lungs were poorly developed and likely caused her to have insufficient oxygen."

Born Sep 16 this year, the cub died less than a week later, leaving zoo officials devastated and searching for answers.

The zoo also said that the cub's mother, Mei Xiang, is back eating her normal diet of bamboo, fruits, vegetables and biscuits.

She is "completely back to her old self. Her hormones have returned to normal levels, as has her behaviour", it added.